I'm probably being dense, but I don't see why there is a contradiction here.

There isn't one, I misread what you had written.

shread wrote:

I wish you could expand on this. The criticism I gave is a common one when directed to biological models, and a most infuriating one to answer, since we (biologists) don't have similar success to physicists in showing the utility of our models. All you have to do is drag out Galileo.

Well, to be fair, biologists abstract away details all the time, even in the more "quantitative" areas. It's often unreasonable to, say, model an enzymatic reaction as a discrete stochastic process--way easier to assume they're continuous functions and use ODEs. A good rule of thumb is: whenever you see a differential equation in a biological model, they're ignoring some complexity.

Nearly every regulation model includes some stuff and ignores other stuff--usually you include stuff your lab (+ collaborators) is set up to measure, and ignore everything else.

I'd say that in both fields, it's a question of whether your model is too simple for the system you're working in. As long as the stuff you're ignoring operates on a scale that's orders of magnitude smaller, you're probably safe.

Well i think it's the world that is being nice to physicists. In physics, something made of many atoms often follows simpler rules than individual atoms do.

In biology there was natural selection to try to make better use of the available complexity - something big and made of many cells can at start act simpler than a single cell, but then it will evolve and make use of the complexity it can attain with many cells. Basically, it's like, if physics was software, you could optimize it a ton by not calculating individual quarks n stuff, and still be close enough even at Newtonian physics level of complexity, and this allows us to, having limited computing power, make really cool technology nonetheless. For biology you can't do that so easily, there's minimum amount of calculations for finding what shape protein will fold into, and this minimum amount is not very small.

Nearly every regulation model includes some stuff and ignores other stuff--usually you include stuff your lab (+ collaborators) is set up to measure, and ignore everything else.

Ahh, the world of science.

That was some hyperbole, but yeah. That's not to say it's a totally ridiculous thing to do--if you can't measure something, you're handwaving anyway. You can only create a model you have support for--you can say "and maybe these other factors are important" but if you have no way to show it, then that's that.

If your experiments have no results using the tools you've got, then you either look for new tools or you look for a new experiment. We're in a very different stage of discovery, compared to physics--there are processes going on that we just don't know about, and some things are totally unknown simply because no one has looked at them yet.

Nearly every regulation model includes some stuff and ignores other stuff--usually you include stuff your lab (+ collaborators) is set up to measure, and ignore everything else.

Ahh, the world of science.

That was some hyperbole, but yeah. That's not to say it's a totally ridiculous thing to do--if you can't measure something, you're handwaving anyway. You can only create a model you have support for--you can say "and maybe these other factors are important" but if you have no way to show it, then that's that.

If your experiments have no results using the tools you've got, then you either look for new tools or you look for a new experiment. We're in a very different stage of discovery, compared to physics--there are processes going on that we just don't know about, and some things are totally unknown simply because no one has looked at them yet.

You've been talking about things several levels of organization below whole organisms in ecosystems. With each increase in level, glitches in lower levels add to uncertainty, although it's clearly not hopeless! (<- Egads, a 'no shit sherlock' statement). I would classify enzymatic kinetics as well characterized, even mathematically, but, as you say, a lot can happen and we probably haven't studied examples of all that can, even for one organism, let alone the tens of millions that are extant.

Especially in biology, a not unproductive research direction is, if you can measure something, you measure the hell out of it, and try to integrate those measurements into the bigger picture. As you start to assemble your measurement protocols, you might have grandiose ideas about how earth shaking they'll be, but reality usually intervenes and you have to settle for the prosaic. Remember when the lac operon was going to tell us how elephants worked? Well, yeah, in part, and a pretty small part, albeit crucial.

I would classify enzymatic kinetics as well characterized, even mathematically, but, as you say, a lot can happen and we probably haven't studied examples of all that can, even for one organism, let alone the tens of millions that are extant.

The kinetics of single reactions are well characterized (in the abstract sense, there are of course still tons of enzymes we haven't measured). Circuits with, say, three nodes are keeping many people busy right now. Kind of amazing how quickly the complexity piles up.

I would classify enzymatic kinetics as well characterized, even mathematically, but, as you say, a lot can happen and we probably haven't studied examples of all that can, even for one organism, let alone the tens of millions that are extant.

The kinetics of single reactions are well characterized (in the abstract sense, there are of course still tons of enzymes we haven't measured). Circuits with, say, three nodes are keeping many people busy right now. Kind of amazing how quickly the complexity piles up.

I was thinking of regulation of activity, as opposed to changing the concentration of an enzyme genetically: substrate/product/inhibitor/stimulator(?) feedback and all that. Just musings with no basis in fact or data.

I was thinking of regulation of activity, as opposed to changing the concentration of an enzyme genetically: substrate/product/inhibitor/stimulator(?) feedback and all that. Just musings with no basis in fact or data.

Oh, in that case I disagree. I wouldn't say we understand it all that well. I mean, we mostly have the concepts you listed down*, but figuring out what a cell can do/is doing with that set of tools is hard.

* Although given recent history I'm not going to rule out yet another method of regulation just yet.

Something I've suspected for a while is that male pattern baldness serves a social function (like silver hair in gorrillas). It seems to neat, orderly, and consistent a pattern to not have some evolved purpose.

Something I've suspected for a while is that male pattern baldness serves a social function (like silver hair in gorrillas). It seems to neat, orderly, and consistent a pattern to not have some evolved purpose.

It serves to offer additional cooling at just about the time of life when one's gut is becoming better insulated.

Something I've suspected for a while is that male pattern baldness serves a social function (like silver hair in gorrillas). It seems to neat, orderly, and consistent a pattern to not have some evolved purpose.

It signals to potential mates that our brains are so powerful that they cut off the nutrient flow to our scalps in order to maintain our superior mental capacity.

Something I've suspected for a while is that male pattern baldness serves a social function (like silver hair in gorrillas). It seems to neat, orderly, and consistent a pattern to not have some evolved purpose.

Few tens thousands years ago and back, anyone who was old enough to be bald, had badass genes, but also lower capacity to care for children, so one can imagine that there would need to be a honest-ish signal for that.

While that's technically correct, it does not solve my conundrum. I can't carry around bare wires and an exposed 8 KV high voltage power supply. It needs to be a compact GM detector. I have one, and a good one, but it has the SBM-20. While a great Russian-made tube, it is 100% glass. It can pickup alpha, although not calibrated, but only if I pop open the device cover and place the source right next to the tube. I need a tube with a mica window, compatible with SBM-20 (read: similar high voltage supply and similar meter calibration).

You can hide the high voltage wires behind metal mesh, or metal mesh + thin plastic wrap if you need it sealed from moisture. Regarding compact, you can make it in what ever size you need, with obvious ramifications (smaller size, fewer alpha tracks to detect).

I don't think that Mars exploration is worthwhile. It appears to me that even if you overcame the huge technical challenges of moving a team of persons and all of the supplies needed to Mars safely (huge problem is the thin atmosphere yet relatively high gravity ratio compared to earth), all get is a desert landscape and air you can't breathe, along with a highly radioactive environment, and the mental challenges of living in such a barren and hostile environment.

It would be wiser IMO to attempt to first robotically terraform Mars, if by some way bringing comets or melting water that is at the ice caps into the atmosphere.

Does there exist sci-fi that has a good understanding of orbital physics? It seems to me that a lot of what passes for sci-fi has a bunch of "space magic", without putting in any of the really interesting physics around planetary motion and how it affects the craft.

I have read Red Mars by Kim Stanley Robinson and it was the more realistic than most, though IMO as it went on it became more "space magic"

Does there exist sci-fi that has a good understanding of orbital physics? It seems to me that a lot of what passes for sci-fi has a bunch of "space magic", without putting in any of the really interesting physics around planetary motion and how it affects the craft.

I have read Red Mars by Kim Stanley Robinson and it was the more realistic than most, though IMO as it went on it became more "space magic"

Titan, by Stephen Baxter. Actually I suspect all of his stuff is along those lines.

Alastair Reynolds generally hews fairly close to "actually possible" as well, albeit in a much farther-future setting.

I just have to say that this thread makes me wish that the fora still had the print view for posts.

Saint wrote:

Isn't Gravity the final force they can't seem to reconcile with the other forces?

I have a completely irrational, utterly ludicrous, obsession to read enough to know how to figure this out.

It's similar to what happened when I learned about Goldbach's Conjecture; it drove me absolutely crazy that no one had come up with a proof for something that seems so simple. It still does; I have a OneNote notebook where I keep snippets I run across that I think may help formulate an accurate proof (this is one of them)

I keep thinking that if the gravity force reconciliation problem were viewed in some completely different or opposite way than it is now...maybe as another aspect of space/time or the speed of light as a constant...it would all fall into place.

So, something i was thinking about: inadequate application of scientific method when it comes to psychological conditions.

Many common medications used to deal with psychological conditions have only a very small effect over placebo; it seems that only a small sub population of those treated actually have a condition that is improved by medication, with the rest being helped equally well by half-placebo - the placebo effect you get when you are made aware there is 50% chance you are in the control group that is receiving placebo. That should not be surprising as it is known that the conditions in question often have non-chemical cause (i.e. some distressing information or imagery) and are conjectured to only sometimes have a chemical cause. Essentially, it is like taking anti-flu medicine for the cough that is usually caused by dust rather than flu. Two distinct disorders with same symptoms, and the medication only helping with one of the disorders.

Furthermore, in presence of side effects, the people experiencing side effects are more certain they are not in the control group, and subsequently are subject to stronger placebo effect, so one should expect a small above-placebo effect even in the drugs that have no effect on the actual condition, just as long as their side effects are sufficiently strong. (One could use toxins as placebo, but then there is the problem with placebo potentially worsening the original condition).

Through the entire history of medicine the most popular remedies have been complete bullshit; the improvement over bullshit came around, largely, from greater understanding of the disease allowing us to cull out the obvious bullshit even before the testing; we do not understand the workings of intelligence very well though, and subsequently some areas of medicine should be expected to stay well behind. If you look at history of medicine and go back as little as 100 years, or even 50 years, you find an enormous amount of what is now recognized as bullshit.

I just have to say that this thread makes me wish that the fora still had the print view for posts.

Saint wrote:

Isn't Gravity the final force they can't seem to reconcile with the other forces?

I have a completely irrational, utterly ludicrous, obsession to read enough to know how to figure this out.

It's similar to what happened when I learned about Goldbach's Conjecture; it drove me absolutely crazy that no one had come up with a proof for something that seems so simple. It still does; I have a OneNote notebook where I keep snippets I run across that I think may help formulate an accurate proof (this is one of them)

I keep thinking that if the gravity force reconciliation problem were viewed in some completely different or opposite way than it is now...maybe as another aspect of space/time or the speed of light as a constant...it would all fall into place.

If you've not seen or read them then Richard Feynmann's series of lectures titled "The Character of Physical Law" might appeal. Especially number 7 "Seeking new laws".

Does there exist sci-fi that has a good understanding of orbital physics? It seems to me that a lot of what passes for sci-fi has a bunch of "space magic", without putting in any of the really interesting physics around planetary motion and how it affects the craft.

I have read Red Mars by Kim Stanley Robinson and it was the more realistic than most, though IMO as it went on it became more "space magic"

Good question! For once I'd like to see proper orbital mechanics in sci-fi. Instead they either treat orbit as open space, or worse yet fly around as if a lifting body in the atmosphere (airplane).

Anecdote: one of the early NASA Gemini missions was supposed to test orbital rendezvous(in preparation for docking). The astronauts on the mission prior to the rendezvous mission spotted their booster stage a few miles away from their capsule, in a similar orbit. They asked for permission to perform an improv rendezvous and station keeping in preparation for next mission. The bosses said yes without consulting the "trench" (flight controllers responsible for retro fire, flight dynamics and the guidance). So astronauts, all of them jet pilots, used little more than their piloting intuition and began to fire thrusters to close in toward the booster. The harder they tried the further away the booster seemed to drift. They were changing their orbital velocity and thus changing their orbit (higher or lower I can't remember). Trench was finally asked about this and their answer was pretty much a "duh".

Some of Clarke's novels deal with more realistic "hard" SF problems - Hammer of God specifically dealt with changing a body's orbit, and IIRC 2001 and 2010 both at least addressed how to properly navigate near a large planetary body. Any "hard" sci-fi should at least make passing reference to this.

Oddly enough, the strategic fleet movements of Mobile Suit Gundam and its UC-era spinoffs tend to square with OM limitations fairly well (with the caveat that the actual engagements don't), but I think that was just coincidental happenstance from trying to make it more like WWII-era fleet movements.

Does there exist sci-fi that has a good understanding of orbital physics? It seems to me that a lot of what passes for sci-fi has a bunch of "space magic", without putting in any of the really interesting physics around planetary motion and how it affects the craft.

I have read Red Mars by Kim Stanley Robinson and it was the more realistic than most, though IMO as it went on it became more "space magic"

Good question! For once I'd like to see proper orbital mechanics in sci-fi. Instead they either treat orbit as open space, or worse yet fly around as if a lifting body in the atmosphere (airplane).

Anecdote: one of the early NASA Gemini missions was supposed to test orbital rendezvous(in preparation for docking). The astronauts on the mission prior to the rendezvous mission spotted their booster stage a few miles away from their capsule, in a similar orbit. They asked for permission to perform an improv rendezvous and station keeping in preparation for next mission. The bosses said yes without consulting the "trench" (flight controllers responsible for retro fire, flight dynamics and the guidance). So astronauts, all of them jet pilots, used little more than their piloting intuition and began to fire thrusters to close in toward the booster. The harder they tried the further away the booster seemed to drift. They were changing their orbital velocity and thus changing their orbit (higher or lower I can't remember). Trench was finally asked about this and their answer was pretty much a "duh".

Which mission was this?

The best guess I have is that what they should have done to reach it was slow down their craft so it would reach a lower orbital. If the stage were slightly in front of them and at a lower altitude, I'm guessing that they hit a booster forward and it took them higher due to higher forward velocity resulting in higher altitude.

Does there exist sci-fi that has a good understanding of orbital physics? It seems to me that a lot of what passes for sci-fi has a bunch of "space magic", without putting in any of the really interesting physics around planetary motion and how it affects the craft.

I have read Red Mars by Kim Stanley Robinson and it was the more realistic than most, though IMO as it went on it became more "space magic"

Good question! For once I'd like to see proper orbital mechanics in sci-fi. Instead they either treat orbit as open space, or worse yet fly around as if a lifting body in the atmosphere (airplane).

Anecdote: one of the early NASA Gemini missions was supposed to test orbital rendezvous(in preparation for docking). The astronauts on the mission prior to the rendezvous mission spotted their booster stage a few miles away from their capsule, in a similar orbit. They asked for permission to perform an improv rendezvous and station keeping in preparation for next mission. The bosses said yes without consulting the "trench" (flight controllers responsible for retro fire, flight dynamics and the guidance). So astronauts, all of them jet pilots, used little more than their piloting intuition and began to fire thrusters to close in toward the booster. The harder they tried the further away the booster seemed to drift. They were changing their orbital velocity and thus changing their orbit (higher or lower I can't remember). Trench was finally asked about this and their answer was pretty much a "duh".

Which mission was this?

The best guess I have is that what they should have done to reach it was slow down their craft so it would reach a lower orbital. If the stage were slightly in front of them and at a lower altitude, I'm guessing that they hit a booster forward and it took them higher due to higher forward velocity resulting in higher altitude.

Try Larry Niven's Smoke Ring series. Much orbital mechanics in the plot due to the setting.

I just have to say that this thread makes me wish that the fora still had the print view for posts.

Saint wrote:

Isn't Gravity the final force they can't seem to reconcile with the other forces?

I have a completely irrational, utterly ludicrous, obsession to read enough to know how to figure this out.

It's similar to what happened when I learned about Goldbach's Conjecture; it drove me absolutely crazy that no one had come up with a proof for something that seems so simple. It still does; I have a OneNote notebook where I keep snippets I run across that I think may help formulate an accurate proof (this is one of them)

I keep thinking that if the gravity force reconciliation problem were viewed in some completely different or opposite way than it is now...maybe as another aspect of space/time or the speed of light as a constant...it would all fall into place.

If you've not seen or read them then Richard Feynmann's series of lectures titled "The Character of Physical Law" might appeal. Especially number 7 "Seeking new laws".

Because they are interesting or because they would quickly dispell my aforementioned crazy idea?

I just have to say that this thread makes me wish that the fora still had the print view for posts.

Saint wrote:

Isn't Gravity the final force they can't seem to reconcile with the other forces?

I have a completely irrational, utterly ludicrous, obsession to read enough to know how to figure this out.

It's similar to what happened when I learned about Goldbach's Conjecture; it drove me absolutely crazy that no one had come up with a proof for something that seems so simple. It still does; I have a OneNote notebook where I keep snippets I run across that I think may help formulate an accurate proof (this is one of them)

I keep thinking that if the gravity force reconciliation problem were viewed in some completely different or opposite way than it is now...maybe as another aspect of space/time or the speed of light as a constant...it would all fall into place.

If you've not seen or read them then Richard Feynmann's series of lectures titled "The Character of Physical Law" might appeal. Especially number 7 "Seeking new laws".

Because they are interesting or because they would quickly dispell my aforementioned crazy idea?

Because they are interesting; give some more techniques to apply and actively encourage the aforementioned crazy idea.